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Life on Earth evolved under a specific set of environmental conditions, including consistent gravitational and magnetic fields. However, planned human missions to Mars in the coming decades will expose terrestrial organisms to radically different conditions, with Martian gravity being approximately 38% of Earth's and a significantly reduced magnetic field. Understanding the combined effects of these factors is crucial, as they may impact biological systems that evolved under different conditions. In this study, we investigated the effects of simulated Martian gravity and hypomagnetic fields on the nematode Caenorhabditis elegans across six generations. We used an integrated experimental setup consisting of clinostats to mimic the reduced Martian gravity, and Merritt coil magnetic cages to model the decreased Martian magnetic fields. We assessed behavioral, morphological, and physiological responses of C. elegans. High-throughput automated assays revealed significant reductions in motor output and morphological dimensions for animals in the Mars treatment compared to matched earth-like controls. We assessed neurological function by means of chemotaxis assays and found a progressive decline in performance for worms raised under the Martian paradigm compared to Earth controls. Our results show that worms grown under Martian-like conditions exhibit progressive physiological alterations across generations, suggesting that the unique environment of Mars might pose challenges to biological function and adaptation. These findings contribute to understanding how living organisms may respond to the combined effects of reduced gravity and hypomagnetic fields, providing insights relevant for future human exploration and potential colonization of Mars.
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This content will become publicly available on May 27, 2026
A Study Demonstrating That Using Gravitational Offset to Prepare Extraterrestrial Mobility Missions Is Misleading
ABSTRACT Recently, there has been a surge of international interest in extraterrestrial exploration targeting the Moon, Mars, the moons of Mars, and various asteroids. This contribution discusses how current state‐of‐the‐art Earth‐based testing for designing rovers and landers for these missions currently leads to overly optimistic conclusions about the behavior of these devices upon deployment on the targeted celestial bodies. The key misconception is that gravitational offset is necessary during theterramechanicstesting of rover and lander prototypes on Earth. The body of evidence supporting our argument is tied to a small number of studies conducted during parabolic flights and insights derived from newly revised scaling laws. We argue that what has prevented the community from fully diagnosing the problem at hand is the absence of effective physics‐based models capable of simulating terramechanics under low‐gravity conditions. We developed such a physics‐based simulator and utilized it to gauge the mobility of early prototypes of the Volatiles Investigating Polar Exploration Rover. This contribution discusses the results generated by this simulator, how they correlate with physical test results from the NASA‐Glenn SLOPE lab, and the fallacy of the gravitational offset in rover and lander testing. The simulator, which is open‐source and publicly available, also supports studies for in situ resource utilization activities, for example, digging, bulldozing, and berming, in low‐gravity environments.
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- Award ID(s):
- 2209791
- PAR ID:
- 10611079
- Editor(s):
- NA
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Journal of Field Robotics
- ISSN:
- 1556-4959
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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